I have had a Navman 2100 for some time now. I have mine close to the compass and do not recall any info about that? It is a great simple unit for a good price. Not too funny that most have issues with the fuel transducer out of the box
. Here is the old post below.
If you want to feed in GPS speed for MPG, the 3100 is the way to go and bigger display. I may upgrade next season ..
old post
Here is a compare thread also;
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